Fault current limiters (FCLs) are used to provide protection against current surges, for example in a power transmission network. Various types of FCLs have been developed over the last several decades, including superconducting fault current limiters (SCFCLs), solid-state fault current limiters, inductive fault current limiters, as well as other varieties that are well known in the art. A power system in which an FCL is implemented may include generation, transmission, and distribution networks that generate and deliver power to various industrial, commercial, and/or residential electrical loads.
A fault current is an abnormal current in an electrical system that may result from a fault in the system, such as a short circuit. A fault current may arise in a system due to any number of events or failures, such as power lines or other system components being damaged by severe weather (e.g. lightning strikes). When such a fault occurs, the fault current limiter acts to protect the system from the fault current. During normal operation, however, it is desired that the fault current limiter will have as little affect on the system being protected as possible.
Thus there is a need for a fault current limiter that has low insertion impedance and causes negligible voltages drop and power loss in the circuit being protected during normal operation but which is still able to protect against fault currents.